It is false, the atomic number is the number of protons and/or electrons in an atom on an element.
Atomic mass Calcium ( Ca) = 40.078 u.m.a
40.078 g --------------- 6.02x10²³ atoms
187 g ------------------- ??
187 x ( 6.02x10²³) / 40.078 =
1.125x10²⁶ / 40.078 = 2.808x10²⁴ atoms
hope this helps!
Vas happenin
Hope your day is going well
Atoms are referred to basic unit of matter
Hope this helps *smiles*
Answer:
no, the sollution will boil at a higher temperature because the density of the sollution will increase when salt is added to it
Answer:
Option D. 30 mL.
Explanation:
Step 1:
The balanced equation for the reaction. This is given below:
HNO3 + KOH —> KNO3 + H2O
From the balanced equation above,
The mole ratio of the acid, nA = 1
The mole ratio of the base, nB = 1
Step 2:
Data obtained from the question. This include the following:
Volume of base, KOH (Vb) =.?
Molarity of base, KOH (Mb) = 0.5M
Volume of acid, HNO3 (Va) = 10mL
Molarity of acid, HNO3 (Ma) = 1.5M
Step 3:
Determination of the volume of the base, KOH needed for the reaction. This can be obtained as follow:
MaVa / MbVb = nA/nB
1.5 x 10 / 0.5 x Vb = 1
Cross multiply
0.5 x Vb = 1.5 x 10
Divide both side by 0.5
Vb = (1.5 x 10) /0.5
Vb = 30mL
Therefore, the volume of the base, KOH needed for the reaction is 30mL.
